The research described herein proposes (1) to investigate three specific problems of primate reproductive physiology which will culminate in successful artificial insemination in the chimpanzee and (2) to provide information, using the chimpanzee as a model, for direct application in the study of specific problems of human reproduction. First, we will develop further our already established technique of rectal probe electroejaculation and determine which combination of stimulus frequency and current provides the greatest yield of semen. Second, we will utilize scanning electron microscopy and light microscopy to examine ultrastructurally the extent to which the large volume of coagulum found in each semen specimen can be enzymatically degraded to yield a large population of motile spermatozoa. Third, we will conduct a series of experimental inseminations followed by timed laparotomies to learn the rate of transport and fate of spermatozoa deposited, near the time of ovulation, in the vagina. Steroid and gonadotropin hormonal data, as well as data on ovarian morphology and cervical mucus ferning and spinnbarkeit, when correlated with genital sexual swelling patterns, will allow a more precise estimation of ovulation time in the female chimpanzee. The information from the above mentioned studies will allow artifical inseminations, some of which have already been done in order to develop the technique, to be successful in initiating pregnancies. Once established, this artifical breeding program will be inexpensive to maintain, and will allow all chimpanzees of breeding age and normal fertility--many of whom because of laboratory rearing away from maternal care have inadequate reproductive behavior--to play a functional role in breeding. This is very necessary in essentially closed colonies in order to maximize genetic diversity, and in colonies such as ours, where natural breeding can provide only half our present animal needs for research and preserving species integrity. Perfection of the electroejaculation technique will allow its adoption to human patients who have spinal cord injuries, with unimpaired fertility but reduced sexual function, and a desire to father children. Details of spermatozoon migration through the chimpanzee female reproductive tract, obtained by experiments inadmissable in man, should provide an indication of the time course of a similar events in the human female.